The present invention relates to an electromagnetic valve, in particular for hydraulic automotive vehicle brake systems with wheel slip control.
German patent application No. 40 30 571 discloses an electromagnetic valve of the type referred to hereinabove which includes a valve housing accommodating a sleeve that houses a magnetic core. Close to the magnetic core, a magnetic armature with a valve closure member is arranged. In the electromagnetically non-energized initial position, the valve closure member closes a valve passage between a first and a second pressure fluid channel in the valve housing under the action of a compression spring. Pressure differences develop in the pressure fluid channels in the valve's closed position downstream and upstream of the valve and can impair the switching speed of the valve. Further, great differences in temperature impair the viscosity of the fluid and take influence on the operation of the valve.
Therefore, an object of the present invention is to improve upon an electromagnetic valve of the type referred to hereinabove to such effect that differential pressures and temperature effects do not impair the operability of the valve in its switching actions so that as constant and as high switching speeds of the valve as possible can be achieved.